In various operations involving the processing or otherwise handling of powdered materials, such materials commonly have been stored and transported in bulk bags which are adapted to be emptied into various types of hoppers. Typically, such bags are equipped with a set of straps at an upper end thereof which may be connected to the blades of a forklift truck or another lifting and transporting device, and a spout at a lower end thereof which may be closed to contain the material within the bag and opened to unload the material. Various means have been employed for closing such spouts. They may be folded closed and maintained in the closed position by a flap, commonly referred to as a“diaper,” overlying the folded spout and releasably secured to the main body portion of the bag, or simply may be releasably tied closed. Such hoppers can be of a variety of configurations, each having an upper inlet in which the lower end of a bag may be positioned and the spout thereof opened to permit the gravity flow of material into the hopper, and a lower outlet often communicable with a material conveying means such as a mechanical or pneumatic conveyor.
In the use of such arrangements of components, it has been the practice to position the bag in a suspended position with the lower end thereof disposed above the hopper, and then have operator reach under the suspended bag to release the spout and thus permit the material in the bag to gravity flow through the spout into the hopper. In such operation, however, it has been found that the operator reaching beneath the suspended bag and manually releasing the spout of the bag from the folded, closed position not only places the operator at risk of physical injury but exposes him to the hazardous effects of dust created by the material flowing out of the bag and into the hopper. In addition, it has been found that the use of such prior art unloading methods and equipment has been inefficient, resulting in a loss of production. Accordingly, it is the principal object of the present invention to provide an improved apparatus for unloading powdered materials from a bulk bag which is safe to handle, less polluting of the ambient atmosphere and more productive in use.